Former and England defender and columnist Martin Keown returned to answer YOUR questions on the big talking points in football.

The Premier League is back after a week of Champions League football as Manchester United and Manchester City struggled in Europe.

United were held to another goalless draw at Old Trafford by PSV while City, who are the only English club guaranteed to reach to the knockout stage, were beaten 1-0 by Juventus.

Table topping Leicester welcome United to the King Power Stadium this weekend while Tottenham host Chelsea in a mouthwatering London derby.

See below to check out Martin's answers to all of your questions.

Martin Keown

Host commentator

Auto-update

13:49

Full-time

That's all for today. Thanks for all your questions this week and please check back next Thursday for another edition of #TackleKeown.

13:47

Last time Chelsea went to White Hart Lane they lost 5-3. Back then Chelsea were playing well. What do you think will happen on Sunday when they face an in-form Spurs team? Nick in Essex

That game was an incredible performance from Tottenham because at that stage of the season, Chelsea looked better than anyone else in the league. Harry Kane was quite magnificent that day and Tottenham will have good memories of that game. Historically, this has always been a very good fixture for Chelsea but I think that’s changed and Tottenham could do some real damage this weekend.

This is a defining game for Chelsea. They got a good win in the Champions League but this game is huge. If Tottenham have designs on the top four then they need to look at this as an absolutely crucial game. They are reaching consistency in their results and performances and a win could finish off Chelsea’s aspirations of making the Champions League.

The feeling in the camp has to be: ‘We’re fighting for our lives to make it so we’re sure as hell not going to let them in.’

Chelsea will see Tottenham as one of their rivals and with two games to play against them, there are six points on offer. If they want to pass Tottenham they need to win both because can they match that consistency that we’ve seen from Tottenham in other games?

This is a very young Tottenham team, which could go against them in the run-in, but they are only gaining experience now and they fear no one. Their Europa League trip to Azerbaijan is far from ideal and a midday kick-off on Sunday is a bit naughty – I’m sure Mourinho will be delighted about that as it could be a saving grace for his side. Whoever’s playing around with these fixtures, they are certainly not helping our teams do well. Tottenham will have to work hard mentally to overcome that obstacle and if they want to win they must start really well against Chelsea. It should be a cracking game.

Harry Kane has an incredible scoring record in London derbies

13:44

Diego Costa and Jose Mourinho are at it again. Do you think Costa will last much longer or will Chelsea look elsewhere? Sam Green, Hampshire

At the end of the day, if Jose Mourinho loses his head then he can’t be unhappy if one of his players does as well. He is big enough to dish it out so he has to be big enough to take it as well. But I think he dealt with it well. He could have taken Costa off, which would have only made him sulk, or, as he said, they could kiss and make up. Jose went the right way for me. He wanted a reaction out of his player and he got one. And I fully expect him to stick by his striker.

But Costa may have lost his way a little bit. Sometimes players want to pick fights with the opposition because it helps get them motivated. Costa is clearly that kind of player but right now it is making him lose his focus. He is there to win games and score goals. Often his macho efforts go way over the top. He is trying to physically embarrass and intimidate the defender to put him down. But the best way to do that is to score goals. Yes, you have to be competitive but with Costa it has all gone too far. For his goal against Norwich last Saturday, he slowed things down and it looked more like a training ground finish. He seemed much calmer and more composed. His celebration was almost muted, as if he was thinking: ‘It’s about time I put one away.’

For top strikers goals are like oxygen. They feed off them and it gives them energy. You see that with Vardy – every time he scores he seems even quicker and sharper. With Costa, as the goals have ebbed away, so has his energy. He needs to get his focus back and start putting them away to reignite his game.

13:31

Can Jurgen Klopp get Liverpool in the Champions League? They were sensational at City. Mark in Chester

I think he can. He can help them to achieve anything and those players must be loving coming into work every day. But I do think Klopp has made the Champions League a real possibility for Liverpool and they will be battling it out with Tottenham. The German has been able to work his magic quickly and actually the 0-0 in his first game at Tottenham looks like a good result for them.

Sometimes with football it can be a little bit fairy-tale. Liverpool fans want a manager they can really believe in. If you go back to Bill Shankly then everything was always geared to the fans. It was all about the people of Liverpool and their shared values. There is a lot of emotion in that part of the world and Klopp seems completely tuned into that. He is also somebody that has a really good set of values as a person. He wants to be a nice guy and he wants to spread that. It is like a family at a football club and the manager’s behaviour translates throughout the club. If he’s optimistic, buoyant and shows belief, then the players start to believe too. I often think that players are a reflection of their manager – in how they behave and treat people.

People might have thought that at the beginning with Klopp it was all talk, and talk is cheap. But so far he has talked the talk and walked the walk. His team’s performances are starting to match his ideas. It was a wonderful performance against Man City and even though it’s only one game, Klopp creates such an energy. Players react to every change of mood and atmosphere within the camp and Klopp’s positivity is rubbing off. They want clear instructions, not doubt or confusion.

It’s not time to overcomplicate things and Klopp is clearly getting that message across in training, and doing so very quickly. Because he knows what he wants, he knows how to get that across to his players. There are no grey areas and it’s starting to show on the pitch.

Jurgen Klopp is getting his message across to the Liverpool players

13:25

It’s a table-topper on Saturday when Leicester play Man United. Who’s going to win? Simon in the UAE

Who’d have thought these two teams would be fighting at the top of the table at this stage of the season? Leicester’s is an incredible story.

I was at this fixture last year when Leicester won 5-3 and I was struck by the atmosphere at the King Power Stadium. It was absolutely rocking and I fully expect the same again on Saturday night. I don’t think things can get much better for Leicester right now and I wonder how many fans are still thinking about winning 12 points to hit the magic number of 40 and avoid relegation! I don’t think Leicester will win the league, and the fixtures have been relatively kind so far, but we keep waiting for them to fall away and it’s not happened.

Jamie Vardy has been grabbing the headlines but other players have been so important. Mahrez is taking second billing but he has been extremely good and everybody is doing their job nicely.

There is a great freedom about Vardy and the way he and Leicester are playing. That wasn’t a fluke win at Newcastle, they battled, earned the right to play and then Vardy ran away with it. I’ve compared him to Ian Rush and I stand by that. Both players are incredible at closing down and have the finishing to match. They are a nuisance. But after Vardy, I think every club worth their salt will be getting out there and looking for the next star from non-League. Every time a player of this quality comes through, it changes the mindset and clubs shouldn’t be afraid to look down the divisions. If a non-League player scores a few goals at the weekend, I wouldn’t be surprised if a few clubs started to take a look. Because Vardy has opened the door and shown the dream is not necessarily over for many players down there.

As for the game, it’s going to be tight. Leicester have scored in every game this season but United have the best defensive record in the league. One of those records could go. Leicester have a team of roadrunners and in their early games in particular they hardly had any possession but kept winning matches. So if United want to play keep-ball, Leicester will be well-used to it. United have also had a Champions League game to contend with this week whereas Leicester will be nice and fresh. And of course Vardy will be desperate to set his own scoring record. It should be a tasty encounter.

Jamie Vardy trains on Thursday ahead of the top-of-the-table clash between Leicester and United

13:18

What do you make of the Jack Grealish story this week? Cara, Newport

Jack has to learn and learn quickly because at the minute nothing seems to sink in. In life you learn from your mistakes and if you keep making them, you’ve only got yourself to blame.

I was an Aston Villa player that was relegated so I know exactly what it’s like to go home on a Saturday night after a bad defeat. I certainly don’t remember going out partying. More often than not I went straight home to bed completely knackered because I was trying to fill holes in that defence. All plans were off if you lost a game of football.

Sometimes I don’t think players understand just how much these kinds of photos hurt the fans. There will be thousands of Villa fans who are Jack’s age, watching on from the terraces and who would give up everything to be in his position. He needs to be made aware of his responsibilities and I have to wonder – does he really love the game? There has been a lot of talk about his international allegiance and playing for England and I think it’s all gone to his head.

As a young player there is often a contradiction when you’re trying to break through. You’ve got to be ruthless and not be afraid to step on people to try and get there. But then once you are in a team, if you want to win anything your mindset has to change – you have to be a real team player. There’s no doubting Jack’s talent – he’s the biggest prospect at the club but he probably still feels like an individual.

I’m sure there will be plenty of people at the academy who are disappointed as well. A lot of people put a lot of work in to get him where he is now. There will be young players wanting to follow his path into the team and with his actions he’s letting people down. The trouble is, he probably doesn’t even realise he’s doing it. I’m sure he just thinks he’s on a night out and there’s nothing wrong. But he needs to be made aware of how it looks because if a football club is a family then he’s letting down the family of Aston Villa.

13:12

That was a big defeat for Aston Villa at Everton. Has your old team-mate Remi Garde got what it takes to save them? Concerned Bill in the Midlands

I watched that game against Everton and it just wasn’t a contest. In the end it was embarrassing for the Villa fans. They did well to draw 0-0 at home with Man City and Garde set up in a similar way to that game, thinking he could absorb that pressure and do something on the break.

I see certain similarities between Garde and Arsene Wenger, but Wenger always tried to win games. It was never about stopping teams, the emphasis was on attack not defence. Villa didn’t have the ambition, inclination or quality to attack at Everton and it cost them. If it was a boxing match the referee would have stopped the fight.

That was a magnificent result. Sam went with three at the back, which is not a system I like but on the night it worked a treat. Though I prefer a back four, sometimes it can be a lonely place at centre back if that unit is not well drilled. But with a three you have bodies around you all the time. You can spread the workload and deal with what’s in your area. It does invites pressure down the sides but it can be a useful option.

I think Younes Kaboul looked unrecognisable on Monday. He has the athleticism to play at full back so he is well-equipped to play in a three and John O’Shea looked much better with two men either side of him. It helped Sunderland look more solid but I do fear teams might exploit them down the side.

Crystal Palace played into their hands with Yannick Bolasie and Wiflried Zaha coming inside rather than stretching them out wide. They didn’t play with their heads. But I have to say I’d still be shocked and surprised if Sunderland stay up. It would certainly rank as one of Big Sam’s greatest achievements if he did it.

Though if he does, he has to keep Jermain Defoe firing. Watching the game I had a sneaky feeling Defoe might win it for them. He still looks quick and sharp, and I don’t think age is an issue with him. If any defenders set to face him soon think he’s past it, think again. But Jermain needs to be motivated. There has been talk of selling him and I think that would be a mistake. If I was a manager competing with Sunderland and Defoe became available, I’d certainly snap him up. But I do wonder if it’s actually Sam being clever. If there is talk of Defoe leaving, it could actually make him more determined to stay and prove himself. Physically he’s fit and raring to go so if he has that hunger and desire, he could be a valuable asset to Sunderland.

Jermain defoe will be key to Sunderland staying in the Premier League

13:01

Why can’t Man City beat the big teams in Europe? Tom, Bedford

To be honest, Tom, I’m not looking to criticise City because I feel they’ve made good progress. To lose 1-0 to last year’s Champions League finalists is no great disgrace. In the first game against the Italians they were 1-0 up and lost but there are signs they can get something from these games. They’re learning all the time and growing in experience in Europe. The trouble is with the investment they have had, fans want them to be up there now.

But I was surprised how they fell apart at the weekend against Liverpool. The two centre backs who played – Mangala and Demichelis – did not look up to it. That for me is the biggest worry with City at the moment. Ideally you want a situation where you have squad players who can step in and cause the manager a real selection issue. With City right now, that’s not the case.

You even want players like Sergio Aguero to feel under pressure because if people are fighting for their place then everybody improves. But the way they lost against Liverpool showed things are not quite right and the squad is not yet strong enough.

Manchester City were beaten 1-0 by Juventus on Wednesday night

12:50

Can Arsenal beat Olympiacos and complete the great escape? Alex in Stretham

It’s certainly going to be a very hard and tough night. Olympiacos is a very difficult place to go and Arsenal have a bad record there. But they’ve done everything they can to get themselves back into it and hopefully it will be a good evening!

I’m not surprised they’ve fought back, though. They had it in them but I do think they were guilty of taking the Champions League for granted. I went to the game in Zagreb when they lost and it was a surreal, unusual atmosphere. There was an athletics track, which I never like and it had that feel of a pre-season friendly. The players weren’t fired up enough. Selection may not have helped in sending out the right message – I feel they were too complacent – but losing that first match suddenly made things an uphill struggle.

Then to lose the second at home in the way they did was unforgivable. You simply can’t do that. With the Champions League, it’s not just a name. You’re playing against champions. Zagreb hadn’t lost for about a year before they played Arsenal and that was the scalp they really wanted. As opposition you have to match that desire. Arsenal were not mentally ready and they have been punished ever since.

As for the shoot-out against Olympiacos, there’s no doubt players like Alexis Sanchez and Mesut Ozil have what it takes to win the game. They were magnificent the other night and I was pleased to see Wenger stick with Joel Campbell. He had one of his better games and the more he plays the more he gets on others’ wavelengths. He missed a sitter at West Brom but Wenger kept him in. That will really help his confidence and once he gets his head up and is more composed it will come together. He offers something a little bit different, certainly a different option to Theo Walcott and the Alex Oxlade-Chamberlain.

One of the big concerns will be the loss of Francis Coquelin. He is such an important player and I was surprised that Mathieu Flamini didn’t get a rest once the job was done on Tuesday because he’s going to have to play now for the next two months. It will be tough in Greece but Arsenal have the quality to come through. They just need to make sure they’re ready, mentally.

Arsenal have played their way back into contention in their Champions League group

12:44

So, yet another United bore draw. Should United fans be worried about their lack of goals? Sarah Scott, London

Definitely. And I have a feeling that some pundits at the moment, especially the former United players are getting fed up of repeating themselves.

There is a real chance for Louis van Gaal to be successful this season – the league is so open – and for former players watching, it must be so frustrating. I think it would only take a few little tweaks to give United a great chance.

Football, essentially, is a numbers game. It’s about balancing the number of players you want to defend and how many you want to throw forward. If you decide to keep six at the back – a back four and two midfielders – then you’ve only got four to play with in attack. If you send both full backs forward, then all of a sudden you’ve got six to choose from further forward and that forces the opposition back.

Whenever you played United in their heyday, they basically played with two wingers on each side – Neville and Beckham on the right and Irwin and Giggs on the left. They would fly forward and force you to run back and deal with them. United dictated to you. Now it’s the other way around.

United are almost inviting the opposition onto them because they don’t flood forward and attack. They have a manager who doesn’t want to overcommit and that is reflected in their game. United used to overwhelm teams, just like Barcelona and Bayern Munich do – look at how much Bayern’s full backs get forward, it’s phenomenal.

Great sides over the years have always been brave enough to throw people forward back themselves to outnumber the opposition. And even if they do overcommit in attack, they are still confident of winning back the ball high up the pitch and punishing teams all over again.

At United right now, nobody wants to stray too far from their starting positions. They are playing far too safe and that’s constricting their attacking play. And, ultimately, it comes down to Van Gaal.

Wayne Rooney struggled again as United drew 0-0 with PSV on Wednesday

12:32

When he spoke at the Oxford Union, Ruud van Nistelrooy said you were one of the toughest defenders he played against. But he also said he was worried you would be jumping all over him because you live in Oxford! How was he to play against? Terry Dawes via email

With Jamie Vardy so much in the news, Ruud’s name has been popping up a lot and I’ve been asked this a few times. Obviously at Arsenal we had a bit of an issue with him but I don’t understand how he isn’t regularly mentioned in the list of the best strikers we’ve seen in the Premier League. Because he was.

I know the likes of Thierry Henry and Alan Shearer scored every kind of goal, and Ruud didn’t score too many from outside the box, but he was such a clever player. He had terrific pace but he was bright and so intelligent with his movements.

I’ll give you an example. In the first phase of play, he would stand deliberately offside. So I’d be watching him on the right side of defence but he’d be about 10 yards behind me. United’s left back would have the ball and suddenly switch play right with a 30-yard diagonal pass to Cristiano Ronaldo, who wasn’t offside. He’d start running at Ashley Cole and all of a sudden I look over my shoulder and see Van Nistelrooy bombing towards goal with a 10-yard head-start on me.

He would cause us a lot of problems. And he was physical when he wanted to be as well. He had a bit of nastiness about him, as did Dennis Bergkamp – the Dutch certainly know how to look after themselves. So the first challenge would often be a strong one but, on other occasions, he would collapse like a pack of cards.

He took penalties and was always looking to improve his goal tally so he wasn’t afraid of trying to win fouls in the area. He also had a calmness and composure in front of goal that puts him ahead of most of the strikers who have played for United in the Premier League. He had a window of opportunity at the club and he made the most of it – 150 goals in 219 games is some strike rate. Maybe because of the way he left United he isn’t more fondly remembered, but he was certainly one of their top strikers.

Ruud van Nistelrooy should be considered one of the best Premier League strikers ever